A third-grade class is using plaster of Paris to make impressions of their hands. Each student needs 12 ounces of plaster to make an impression. There are a total of 20 students in the class. How many pounds of plaster will the teacher need for the activity?

15 pounds of plaster

Step-by-step explanation:

First, convert ounces to pounds.

In 1 pound, there are 16 ounces. Create a proportion to convert 12 ounces to pounds.

=

Cross multiply and solve for x:

16x = 12

x = 0.75

So, each student will need 0.75 pounds of plaster. Multiply this by 20 to find the total amount the teacher will need:

20(0.75)

= 15

So, the teacher will need 15 pounds of plaster

x/3-10=8

x/3=18

x=48

1st integer x

2nd integer x+1

3rd integer x+2

4th integer x+3

x+x+1 +x+2+x+3 =74

combine like terms

4x+6 = 74

subtract 6 from each side

4x = 68

x = 17

the integers are 17,18,19,20